There are many different locating technologies and techniques used for underground pipes and cables. The main equipment and tools that have proven to work over many years and situations are listed below.
- Available Existing Information (Maps)
- GPR (Ground Penetrating Radar)
- Acoustic Location (Sound)
- Infra Red Imaging (Thermal)
- Electromagnetic Locating (EM)
Available Existing Information
Gathering Maps and Drawings is one of the first steps to understand what utility services may lay beneath. These can usually be obtained by property owners, utility owners, local council and governments, surveyors and dial before you dig or one call services. Remember this information is classed as (D) as of AS5488, and should never be assumed to be a complete picture of what utilities are underground, this information can be inaccurate and should always be verified before planning or construction projects. However this information can be very useful for saving time and can give you a ruff idea of what to expect moving forward with your project.
Ground Penetrating Radar
GPR or Ground Penetrating Radar for geophysical underground investigation or pipe locating has been around for some time, and has been development and refined over the years to be better and better. However this technology and technique is considered to still be a CLASS D as of AS5488 standards. The reason being is that this can only give you contrast on what is scanned and doesn’t not verify weather a utility is below or not. The GPR can struggle under unfavorable condition’s such as ground with many rocks or obstructions, to other unfavorable soil conditions. These can detect meters into the earth and are many used to confirm known utilities. It is good to use for final clearance checks and confirmation of utilities that cannot be found with em locators or other techniques or technologies.
Acoustic Location (Sound)
Good method for locating accessible plastic pipes. You can use a screwdriver tapping on a conduit to verify connection between stormwater and other pipes that carry sound. Plastic, Metallic, stormwater, sewer, you name it this will locate it. With the use of acoustic technology this machines locates airspace or the hollow section of the pipe by reflecting sound back to the receiver. With the ability to work in all soil types makes this machine a handy tool.
Infra-Red Imaging (Thermal)
The temperature of underground utilities can vary from the surrounding soil conditions, with this basic understanding, infrared imaging cameras can be useful for locating buried pipes and cables. If the contrast of temperature is not significant, it becomes hard to use. This is usually due to environmental factors like being outside with sunlight and shade, causing the technology to become unclear. However this technology has been proven useful for finding sewer leaks, indoor locating, void detection and locating heating and cooling pipes.
Electromagnetic Locating (EM)
Believe it or not, This technology has been used for locating underground pipes for over 100 years, (c.1910). It has proven to be universally useful when locating buried pipes and cables, and is a key piece of tech for locators. It is used to search, trace and identify utility service lines by using electromagnetic signal transmitters and receivers. It can trace almost any metallic pipe or cable with little knowledge, however in congested areas it can be challenging and more experience is needed for accurate results. It can detect plastic or non-metallic pipes, this problem can be solved with trace-wires and rods if access is available. It can also be used in most soil conditions and even in water.
This is not medical advice. This post is inline with covid masks for mandatory guidelines for Australia. For more information on mask guideline for Covid 19 masks for Australia, visit the link...
This information has been created for and applies to Utility Locators and New South Wales Fire Services (NSWFS), Australia. Disclaimer: All efforts have been made to give accurate information, of...